I'm not trying to argue.. I'm trying to explain. Your arguing several points that I've already made
Of course a heater will over heat.. the redundant safety systems are designed to shut it down if it does before catastrophic failure. Even a heater 10-15 years old has these features.
What were missing are symptoms of a heater that's over heating.. Like a temp/pressure relief valve that is tripping. Higher pressure throughout the whole house (I'm sure you understand how adding heat to a closed, pressurized system affects things, so ill skip that lesson)Also, there is no mention of extremely hot water either. As long has this has been going on, a heater stuck wide open would have melted something by now
What we have is a faucet, that has been replaced and both have "air" on the hot side and reduced pressure.. There was mention of the same symptoms in another room but couldn't confirm... Your welcome to read back through my post. I've made several suggestions as to a cause
I misread your post about the air relief valve.. I apologize.
There are several easy ways to diagnose these issues but I'm shooting from the hip working off the info provided.. The same as you. You could be right.. I could be right.. Or we could have both failed miserably
BROTHERTURTLE... I apologize for the highjack, I hope you get the issue resolved
